Kant, We need consistency

IF
with
Epicurus we make virtue determine the will only by means of the
pleasure it promises, we cannot afterwards blame him for holding that
this pleasure is of the same kind as those of the coarsest senses. For
we have no reason whatever to charge him with holding that the ideas
by which this feeling is excited in us belong merely to the bodily
senses. As far as can be conjectured, he sought the source of many of
them in the use of the higher cognitive faculty, but this did not
prevent him, and could not prevent him, from holding on the principle
above stated, that the pleasure itself which those intellectual ideas
give us, and by which alone they can determine the will, is just of
the same kind. Consistency is the highest obligation of a philosopher,
and yet the most rarely found. The
ancient Greek schools give us more
examples of it than we find in our syncretistic age, in which a
certain shallow and dishonest system of compromise of contradictory
principles is devised, because it commends itself better to a public
which is content to know something of everything and nothing
thoroughly, so as to please every party.